Adjusting repeater gain based on antenna feedback path loss

ABSTRACT

Technology for a repeater is disclosed. The repeater can include a first port and a second port. The repeater can include a transmitter communicatively coupled to the first port and a receiver communicatively coupled to the second port. The transmitter can transmit a path loss signal. The receiver can receive the path loss signal transmitted by the transmitter. The repeater can include a controller. The controller can identify a first power level of the signal transmitted from the transmitter. The controller can identify a second power level of the signal received at the receiver. The controller can determine an antenna feedback path loss of the repeater based on the first power level and the second power level. The controller can set a maximum gain level for the repeater based on the antenna feedback path loss to avoid an oscillation in the repeater.

RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional PatentApplication No. 62/840,270, filed Apr. 29, 2019 with a docket number of3969-179.PROV, the entire specification of which is hereby incorporatedby reference in its entirety for all purposes.

BACKGROUND

Signal boosters and repeaters can be used to increase the quality ofwireless communication between a wireless device and a wirelesscommunication access point, such as a cell tower. Signal boosters canimprove the quality of the wireless communication by amplifying,filtering, and/or applying other processing techniques to uplink anddownlink signals communicated between the wireless device and thewireless communication access point.

As an example, the signal booster can receive, via an antenna, downlinksignals from the wireless communication access point. The signal boostercan amplify the downlink signal and then provide an amplified downlinksignal to the wireless device. In other words, the signal booster canact as a relay between the wireless device and the wirelesscommunication access point. As a result, the wireless device can receivea stronger signal from the wireless communication access point.Similarly, uplink signals from the wireless device (e.g., telephonecalls and other data) can be directed to the signal booster. The signalbooster can amplify the uplink signals before communicating, via anantenna, the uplink signals to the wireless communication access point.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the disclosure will be apparent from thedetailed description which follows, taken in conjunction with theaccompanying drawings, which together illustrate, by way of example,features of the disclosure; and, wherein:

FIG. 1 illustrates a signal booster in communication with a wirelessdevice and a base station in accordance with an example;

FIG. 2 illustrates a repeater in accordance with an example;

FIG. 3 illustrates a repeater operable to set a gain level based on anantenna feedback path loss in accordance with an example;

FIG. 4 illustrates a repeater operable to set a gain level based on anantenna feedback path loss in accordance with an example;

FIG. 5 depicts functionality of a repeater in accordance with anexample;

FIG. 6 depicts functionality of a repeater in accordance with anexample;

FIG. 7 depicts functionality of a repeater in accordance with anexample; and

FIG. 8 illustrates a wireless device in accordance with an example.

Reference will now be made to the exemplary embodiments illustrated, andspecific language will be used herein to describe the same. It willnevertheless be understood that no limitation of the scope of theinvention is thereby intended.

DETAILED DESCRIPTION

Before the present invention is disclosed and described, it is to beunderstood that this invention is not limited to the particularstructures, process steps, or materials disclosed herein, but isextended to equivalents thereof as would be recognized by thoseordinarily skilled in the relevant arts. It should also be understoodthat terminology employed herein is used for the purpose of describingparticular examples only and is not intended to be limiting. The samereference numerals in different drawings represent the same element.Numbers provided in flow charts and processes are provided for clarityin illustrating steps and operations and do not necessarily indicate aparticular order or sequence.

EXAMPLE EMBODIMENTS

An initial overview of technology embodiments is provided below and thenspecific technology embodiments are described in further detail later.This initial summary is intended to aid readers in understanding thetechnology more quickly but is not intended to identify key features oressential features of the technology nor is it intended to limit thescope of the claimed subject matter.

FIG. 1 illustrates an exemplary signal booster 120 in communication witha wireless device 110 and a base station 130. The signal booster 120 canbe referred to as a repeater. A repeater can be an electronic deviceused to amplify (or boost) signals. The signal booster 120 (alsoreferred to as a cellular signal amplifier) can improve the quality ofwireless communication by amplifying, filtering, and/or applying otherprocessing techniques via a signal amplifier 122 to uplink signalscommunicated from the wireless device 110 to the base station 130 and/ordownlink signals communicated from the base station 130 to the wirelessdevice 110. In other words, the signal booster 120 can amplify or boostuplink signals and/or downlink signals bi-directionally. In one example,the signal booster 120 can be at a fixed location, such as in a home oroffice. Alternatively, the signal booster 120 can be attached to amobile object, such as a vehicle or a wireless device 110.

In one configuration, the signal booster 120 can include an integrateddevice antenna 124 (e.g., an inside antenna or a coupling antenna) andan integrated node antenna 126 (e.g., an outside antenna). Theintegrated node antenna 126 can receive the downlink signal from thebase station 130. The downlink signal can be provided to the signalamplifier 122 via a second coaxial cable 127 or other type of radiofrequency connection operable to communicate radio frequency signals.The signal amplifier 122 can include one or more cellular signalamplifiers for amplification and filtering. The downlink signal that hasbeen amplified and filtered can be provided to the integrated deviceantenna 124 via a first coaxial cable 125 or other type of radiofrequency connection operable to communicate radio frequency signals.The integrated device antenna 124 can wirelessly communicate thedownlink signal that has been amplified and filtered to the wirelessdevice 110.

Similarly, the integrated device antenna 124 can receive an uplinksignal from the wireless device 110. The uplink signal can be providedto the signal amplifier 122 via the first coaxial cable 125 or othertype of radio frequency connection operable to communicate radiofrequency signals. The signal amplifier 122 can include one or morecellular signal amplifiers for amplification and filtering. The uplinksignal that has been amplified and filtered can be provided to theintegrated node antenna 126 via the second coaxial cable 127 or othertype of radio frequency connection operable to communicate radiofrequency signals. The integrated device antenna 126 can communicate theuplink signal that has been amplified and filtered to the base station130.

In one example, the signal booster 120 can filter the uplink anddownlink signals using any suitable analog or digital filteringtechnology including, but not limited to, surface acoustic wave (SAW)filters, bulk acoustic wave (BAW) filters, film bulk acoustic resonator(FBAR) filters, ceramic filters, waveguide filters or low-temperatureco-fired ceramic (LTCC) filters.

In one example, the signal booster 120 can send uplink signals to a nodeand/or receive downlink signals from the node. The node can comprise awireless wide area network (WWAN) access point (AP), a base station(BS), an evolved Node B (eNB), a baseband unit (BBU), a remote radiohead (RRH), a remote radio equipment (RRE), a relay station (RS), aradio equipment (RE), a remote radio unit (RRU), a central processingmodule (CPM), or another type of WWAN access point.

In one configuration, the signal booster 120 used to amplify the uplinkand/or a downlink signal is a handheld booster. The handheld booster canbe implemented in a sleeve of the wireless device 110. The wirelessdevice sleeve can be attached to the wireless device 110, but can beremoved as needed. In this configuration, the signal booster 120 canautomatically power down or cease amplification when the wireless device110 approaches a particular base station. In other words, the signalbooster 120 can determine to stop performing signal amplification whenthe quality of uplink and/or downlink signals is above a definedthreshold based on a location of the wireless device 110 in relation tothe base station 130.

In one example, the signal booster 120 can include a battery to providepower to various components, such as the signal amplifier 122, theintegrated device antenna 124 and the integrated node antenna 126. Thebattery can also power the wireless device 110 (e.g., phone or tablet).Alternatively, the signal booster 120 can receive power from thewireless device 110.

In one configuration, the signal booster, also referred to as a repeater120, can be a Federal Communications Commission (FCC)-compatibleconsumer repeater. As a non-limiting example, the repeater 120 can becompatible with FCC Part 20 or 47 Code of Federal Regulations (C.F.R.)Part 20.21 (Mar. 21, 2013). In addition, the handheld booster canoperate on the frequencies used for the provision of subscriber-basedservices under parts 22 (Cellular), 24 (Broadband PCS), 27 (AWS-1, 700megahertz (MHz) Lower A-E Blocks, and 700 MHz Upper C Block), and 90(Specialized Mobile Radio) of 47 C.F.R. The repeater 120 can beconfigured to automatically self-monitor its operation to ensurecompliance with applicable noise and gain limits. The repeater 120 caneither self-correct or shut down automatically if the repeater'soperations violate the regulations defined in 47 CFR Part 20.21. While arepeater that is compatible with FCC regulations is provided as anexample, it is not intended to be limiting. The repeater can beconfigured to be compatible with other governmental regulations based onthe location where the repeater is configured to operate.

In one configuration, the repeater 120 can improve the wirelessconnection between the wireless device 210 and the base station 230(e.g., cell tower) or another type of wireless wide area network (WWAN)access point (AP) by amplifying desired signals relative to a noisefloor. The repeater 120 can boost signals for cellular standards, suchas the Third Generation Partnership Project (3GPP) Long Term Evolution(LTE) Release 8, 9, 10, 11, 12, 13, 14, 15, or 16 standards or Instituteof Electronics and Electrical Engineers (IEEE) 802.16. In oneconfiguration, the repeater 120 can boost signals for 3GPP LTE Release16.1.0 (March 2019) or other desired releases.

The repeater 120 can boost signals from the 3GPP Technical Specification(TS) 36.101 (Release 16 Jan. 2019) bands, referred to as LTE frequencybands. For example, the repeater 120 can boost signals from one or moreof the LTE frequency bands: 2, 4, 5, 12, 13, 17, 25, and 26. Inaddition, the repeater 120 can boost selected frequency bands based onthe country or region in which the repeater is used, including any ofbands 1-85 or other bands, as disclosed in 3GPP TS 36.104 V16.1.0 (March2019), and depicted in Table 1:

TABLE 1 LTE Uplink (UL) operating band Downlink (DL) operating bandOperating BS receive UE transmit BS transmit UE receive Duplex BandF_(UL)_low-F_(UL)_high F_(DL)_low-F_(DL)_high Mode  1 1920 MHz-1980 MHz2110 MHz-2170 MHz FDD  2 1850 MHz-1910 MHz 1930 MHz-1990 MHz FDD  3 1710MHz-1785 MHz 1805 MHz-1880 MHz FDD  4 1710 MHz-1755 MHz 2110 MHz-2155MHz FDD  5 824 MHz-849 MHz 869 MHz-894 MHz FDD  6 830 MHz-840 MHz 875MHz-885 MHz FDD (NOTE 1)  7 2500 MHz-2570 MHz 2620 MHz-2690 MHz FDD  8880 MHz-915 MHz 925 MHz-960 MHz FDD  9 1749.9 MHz-1784.9 MHz 1844.9MHz-1879.9 MHz FDD 10 1710 MHz-1770 MHz 2110 MHz-2170 MHz FDD 11 1427.9MHz-1447.9 MHz 1475.9 MHz-1495.9 MHz FDD 12 699 MHz-716 MHz 729 MHz-746MHz FDD 13 777 MHz-787 MHz 746 MHz-756 MHz FDD 14 788 MHz-798 MHz 758MHz-768 MHz FDD 15 Reserved Reserved FDD 16 Reserved Reserved FDD 17 704MHz-716 MHz 734 MHz-746 MHz FDD 18 815 MHz-830 MHz 860 MHz-875 MHz FDD19 830 MHz-845 MHz 875 MHz-890 MHz FDD 20 832 MHz-862 MHz 791 MHz-821MHz FDD 21 1447.9 MHz-1462.9 MHz 1495.9 MHz-1510.9 MHz FDD 22 3410MHz-3490 MHz 3510 MHz-3590 MHz FDD 23¹ 2000 MHz-2020 MHz 2180 MHz-2200MHz FDD 24 1626.5 MHz-1660.5 MHz 1525 MHz-1559 MHz FDD 25 1850 MHz-1915MHz 1930 MHz-1995 MHz FDD 26 814 MHz-849 MHz 859 MHz-894 MHz FDD 27 807MHz-824 MHz 852 MHz-869 MHz FDD 28 703 MHz-748 MHz 758 MHz-803 MHz FDD29 N/A 717 MHz-728 MHz FDD (NOTE 2) 30 2305 MHz-2315 MHz 2350 MHz-2360MHz FDD 31 452.5 MHz-457.5 MHz 462.5 MHz-467.5 MHz FDD 32 N/A 1452MHz-1496 MHz FDD (NOTE 2) 33 1900 MHz-1920 MHz 1900 MHz-1920 MHz TDD 342010 MHz-2025 MHz 2010 MHz-2025 MHz TDD 35 1850 MHz-1910 MHz 1850MHz-1910 MHz TDD 36 1930 MHz-1990 MHz 1930 MHz-1990 MHz TDD 37 1910MHz-1930 MHz 1910 MHz-1930 MHz TDD 38 2570 MHz-2620 MHz 2570 MHz-2620MHz TDD 39 1880 MHz-1920 MHz 1880 MHz-1920 MHz TDD 40 2300 MHz-2400 MHz2300 MHz-2400 MHz TDD 41 2496 MHz-2690 MHz 2496 MHz-2690 MHz TDD 42 3400MHz-3600 MHz 3400 MHz-3600 MHz TDD 43 3600 MHz-3800 MHz 3600 MHz-3800MHz TDD 44 703 MHz-803 MHz 703 MHz-803 MHz TDD 45 1447 MHz-1467 MHz 1447MHz-1467 MHz TDD 46 5150 MHz-5925 MHz 5150 MHz-5925 MHz TDD (NOTE 3,NOTE 4) 47 5855 MHz-5925 MHz 5855 MHz-5925 MHz TDD 48 3550 MHz-3700 MHz3550 MHz-3700 MHz TDD 49 3550 MHz-3700 MHz 3550 MHz-3700 MHz TDD (NOTE8) 50 1432 MHz-1517 MHz 1432 MHz-1517 MHz TDD 51 1427 MHz-1432 MHz 1427MHz-1432 MHz TDD 52 3300 MHz-3400 MHz 3300 MHz-3400 MHz TDD 53 2483.5MHz-2495 MHz  2483.5 MHz-2495 MHz  TDD 65 1920 MHz-2010 MHz 2110MHz-2200 MHz FDD 66 1710 MHz-1780 MHz 2110 MHz-2200 MHz FDD (NOTE 5) 67N/A 738 MHz-758 MHz FDD (NOTE 2) 68 698 MHz-728 MHz 753 MHz-783 MHz FDD69 N/A 2570 MHz-2620 MHz FDD (NOTE 2) 70 1695 MHz-1710 MHz 1995 MHz-2020MHz FDD⁶ 71 663 MHz-698 MHz 617 MHz-652 MHz FDD 72 451 MHz-456 MHz 461MHz-466 MHz FDD 73 450 MHz-455 MHz 460 MHz-465 MHz FDD 74 1427 MHz-1470MHz 1475 MHz-1518 MHz FDD 75 N/A 1432 MHz-1517 MHz FDD (NOTE 2) 76 N/A1427 MHz-1432 MHz FDD (NOTE 2) 85 698 MHz-716 MHz 728 MHz-746 MHz FDD(NOTE 1): Band 6, 23 are not applicable. (NOTE 2): Restricted to E-UTRAoperation when carrier aggregation is configured. The downlink operatingband is paired with the uplink operating band (external) of the carrieraggregation configuration that is supporting the configured Pcell. (NOTE3): This band is an unlicensed band restricted to licensed-assistedoperation using Frame Structure Type 3. (NOTE 4): Band 46 is dividedinto four sub-bands as in Table 5.5-1A. (NOTE 5): The range 2180-2200MHz of the DL operating band is restricted to E-UTRA operation whencarrier aggregation is configured. (NOTE 6): The range 2010-2020 MHz ofthe DL operating band is restricted to E-UTRA operation when carrieraggregation is configured and TX-RX separation is 300 MHz. The range2005-2020 MHz of the DL operating band is restricted to E-UTRA operationwhen carrier aggregation is configured and TX-RX separation is 295 MHz.(NOTE 7): Void (NOTE 8): This band is restricted to licensed-assistedoperation using Frame Structure Type 3.

In another configuration, the repeater 120 can boost signals from the3GPP Technical Specification (TS) 38.104 (Release 15 Jan. 2019) bands,referred to as 5G frequency bands. In addition, the repeater 120 canboost selected frequency bands based on the country or region in whichthe repeater is used, including any of bands n1-n86 in frequency range 1(FR1), n257-n261 in frequency range 2 (FR2), or other bands, asdisclosed in 3GPP TS 38.104 V15.5.0 (March 2019), and depicted in Table2 and Table 3:

TABLE 2 NR Uplink (UL) operating band Downlink (DL) operating bandoperating BS receive/UE transmit BS transmit/UE receive Duplex bandF_(UL, low)-F_(UL, high) F_(DL, low)-F_(DL, high) Mode n1 1920 MHz-1980MHz 2110 MHz-2170 MHz FDD n2 1850 MHz-1910 MHz 1930 MHz-1990 MHz FDD n31710 MHz-1785 MHz 1805 MHz-1880 MHz FDD n5 824 MHz-849 MHz 869 MHz-894MHz FDD n7 2500 MHz-2570 MHz 2620 MHz-2690 MHz FDD n8 880 MHz-915 MHz925 MHz-960 MHz FDD n12 699 MHz-716 MHz 729 MHz-746 MHz FDD n20 832MHz-862 MHz 791 MHz-821 MHz FDD n25 1850 MHz-1915 MHz 1930 MHz-1995 MHzFDD n28 703 MHz-748 MHz 758 MHz-803 MHz FDD n34 2010 MHz-2025 MHz 2010MHz-2025 MHz TDD n38 2570 MHz-2620 MHz 2570 MHz-2620 MHz TDD n39 1880MHz-1920 MHz 1880 MHz-1920 MHz TDD n40 2300 MHz-2400 MHz 2300 MHz-2400MHz TDD n41 2496 MHz-2690 MHz 2496 MHz-2690 MHz TDD n50 1432 MHz-1517MHz 1432 MHz-1517 MHz TDD n51 1427 MHz-1432 MHz 1427 MHz-1432 MHz TDDn65 1920 MHz-2010 MHz 2110 MHz-2200 MHz FDD n66 1710 MHz-1780 MHz 2110MHz-2200 MHz FDD n70 1695 MHz-1710 MHz 1995 MHz-2020 MHz FDD n71 663MHz-698 MHz 617 MHz-652 MHz FDD n74 1427 MHz-1470 MHz 1475 MHz-1518 MHzFDD n75 N/A 1432 MHz-1517 MHz SDL n76 N/A 1427 MHz-1432 MHz SDL n77 3300MHz-4200 MHz 3300 MHz-4200 MHz TDD n78 3300 MHz-3800 MHz 3300 MHz-3800MHz TDD n79 4400 MHz-5000 MHz 4400 MHz-5000 MHz TDD n80 1710 MHz-1785MHz N/A SUL n81 880 MHz-915 MHz N/A SUL n82 832 MHz-862 MHz N/A SUL n83703 MHz-748 MHz N/A SUL n84 1920 MHz-1980 MHz N/A SUL n86 1710 MHz-1780MHz N/A SUL

TABLE 3 Uplink (UL) and Downlink (DL) operating band BS transmit/receiveNR UE transmit/receive operating F_(UL, low)-F_(UL, high) Duplex bandF_(DL, low)-F_(DL, high) Mode n257 26500 MHz-29500 MHz TDD n258 24250MHz-27500 MHz TDD n260 37000 MHz-40000 MHz TDD n261 27500 MHz-28350 MHzTDD

The number of 3GPP LTE or 5G frequency bands and the level of signalimprovement can vary based on a particular wireless device, cellularnode, or location. Additional domestic and international frequencies canalso be included to offer increased functionality. Selected models ofthe signal booster 120 can be configured to operate with selectedfrequency bands based on the location of use. In another example, thesignal booster 120 can automatically sense from the wireless device 110or base station 130 (or GPS, etc.) which frequencies are used, which canbe a benefit for international travelers.

In one configuration, multiple signal boosters can be used to amplify ULand DL signals. For example, a first signal booster can be used toamplify UL signals and a second signal booster can be used to amplify DLsignals. In addition, different signal boosters can be used to amplifydifferent frequency ranges.

In one configuration, the signal booster 120 can be configured toidentify when the wireless device 110 receives a relatively strongdownlink signal. An example of a strong downlink signal can be adownlink signal with a signal strength greater than approximately −80dBm. The signal booster 120 can be configured to automatically turn offselected features, such as amplification, to conserve battery life. Whenthe signal booster 120 senses that the wireless device 110 is receivinga relatively weak downlink signal, the integrated booster can beconfigured to provide amplification of the downlink signal. An exampleof a weak downlink signal can be a downlink signal with a signalstrength less than −80 dBm.

FIG. 2 illustrates an exemplary repeater 200 (or signal booster). Therepeater 200 can include a first antenna 210 communicatively coupled toa first port 212, and a second antenna 220 communicatively coupled to asecond port 222. For example, the first antenna 210 can be an insideantenna or server antenna, and the second antenna 220 can be an outsideantenna or donor antenna. A first duplexer 214 can be communicativelycoupled to the first port 212 and the first antenna 210, and a secondduplexer 224 can be communicatively coupled to the second port 222 andthe second antenna 220.

In one example, the repeater 200 can include an uplink signal path and adownlink signal path. The uplink signal path and the downlink signalpath can be communicatively coupled between the first duplexer 214 andthe second duplexer 224. In this example, the first duplexer 214 and thesecond duplexer 224 can be dual-input single-output (DISO) analogbandpass filters. In one example, the uplink signal path and thedownlink signal path can each include one or more amplifiers (e.g., lownoise amplifiers (LNAs), power amplifiers (PAs)) and one or morebandpass filters. The bandpass filters can be single-input single-output(SISO) analog bandpass filters.

In one example, the uplink signal path and the downlink signal path caneach include a variable attenuator. The variable attenuator can increaseor decrease an amount of attenuation for a specific band (or frequencyrange) in the uplink signal path or the downlink signal path,respectively. The variable attenuator can be increased in order todecrease a gain for a given band (or frequency range) in a respectivesignal path, or the variable attenuator can be decreased in order toincrease a gain for a given band (or frequency range) in a respectivesignal path.

In one example, the second antenna 220 of the repeater 200 can receive adownlink signal from a base station (not shown). The downlink signal canbe passed from the second antenna 220 to the second duplexer 224. Thesecond duplexer 224 can direct the downlink signal to the downlinksignal path. The downlink signal can be amplified and filtered using oneor more amplifiers and one or more filters, respectively, on thedownlink signal path. The downlink signal (which has been amplified andfiltered) can be directed to the first duplexer 214, and then to thefirst antenna 210 of the repeater 200. The first antenna 210 cantransmit the downlink signal to a mobile device (not shown).

In another example, the first antenna 210 can receive an uplink signalfrom the mobile device. The uplink signal can be passed from the firstantenna 210 to the first duplexer 214. The first duplexer 214 can directthe uplink signal to the uplink signal path. The uplink signal can beamplified and filtered using one or more amplifiers and one or morefilters, respectively, on the uplink signal path. The uplink signal(which has been amplified and filtered) can be directed to the secondduplexer 224, and then to the second antenna 200 of the repeater 200.The second antenna 200 can transmit the uplink signal to the basestation.

In one configuration, the repeater 200 can include a controller 260. Thecontroller 260 can include a microcontroller or a discrete electricalcircuit. The controller 260 can be configured to reduce oscillation inthe repeater 200. Generally speaking, the oscillation can be createdwhen the first antenna 210 and the second antenna 220 are located withina defined distance from each other, such that a level of boosteramplification is greater than an antenna feedback path loss between thefirst and second antennas 210, 220 and a positive feedback loop exists.With repeaters, two antennas that are within a defined distance fromeach other can produce an RF squeal.

From an installation perspective, a customer may install repeaterantennas relatively close to each other (e.g., due to constraints in ahome), but a greater gain of the repeater typically necessitates thatthe antennas be installed further away from each other. When antennasare installed relatively close to each other, the oscillation can occurin either a downlink path or an uplink path. In some cases, downlinkand/or uplink signals can be analyzed to determine the presence of orconfirm an oscillation created by an amplifier in the repeater.

In one configuration, a repeater (or signal booster) can receive andtransmit data on a same frequency range. When a data transmission from atransmit antenna of the repeater is picked up or detected by a receiveantenna of the repeater, the repeater can oscillate and malfunction whena repeater gain exceeds a feedback path propagation loss (also known asantenna feedback path loss) of the repeater. The antenna feedback pathloss can refer to the reduction in power density (attenuation) of anelectromagnetic wave as it propagates through space. In other words,when the data transmission travels from the transmit antenna to thereceive antenna, the reduction in power density of the data transmissioncan be referred to as the antenna feedback path loss. When that antennafeedback path loss is less than the repeater's gain, an oscillation canbe caused in the repeater. The oscillation can overload a carriernetwork and cause the repeater to be ineffective.

In one example, the FCC Consumer Booster rules limit a number ofoscillations for a repeater before the repeater is to be manually reset.For example, the FCC Consumer Booster rules can limit the repeater tofive oscillations, at which point the repeater is to be shut downcompletely or manually reset. The manual reset can involve a userunplugging the repeater and plugging the repeater back in. As a result,generally when the repeater detects an oscillation, the repeater candecrease its gain or shut off completely. For example, when theoscillation is detected, the repeater can be shut off for 60-70 seconds,and when five oscillations occur, the repeater can be manually reset.The repeater does not typically try to increase its gain after theoscillation (other than applying the bump-up to check the oscillationmargin) to avoid causing another oscillation. Even if the repeater doesincrease its gain, the repeater is still limited to the number ofoscillations defined by the FCC Consumer Booster rules.

In past solutions, the repeater would initiate or force an oscillationin order to determine that the repeater oscillated, and in order todetermine the oscillation margin. In other words, previous oscillationdetection techniques involved initiating or forcing the oscillation. Inthis process, the noise floor would start to increase due to feedbackpaths, even before the oscillation occurred.

As an example, in past solutions, if a repeater system was installed anda user walked next to or past one of the antennas of the repeater, thismight have caused an oscillation in the repeater due to a new feedbackpath. The repeater would trigger an oscillation and reduce its gain orshut off. In past solutions, the repeater would reduce gain or shut offand not attempt to increase the gain, in order to avoid causing anoscillation and reaching the FCC limit of five oscillations beforehaving to manually reset. In a busy environment, users might walk by therepeater several times a day, and those kinds of disruptions would causethe repeater to operate often at the reduced gain.

In the present technology, a repeater gain and oscillation margin can beset without initiating or forcing an oscillation in the repeater.Setting the repeater gain and oscillation margin without forcing theoscillation can be beneficial for protecting the network and keeping therepeater on for an increased period of time (since the repeater is notforced to shut down after five oscillations). In addition, repeater gainand performance can be dynamically maximized, as the repeater canincrease its gain when an antenna feedback path loss increases.

In the present technology, setting the repeater's gain while avoiding anoscillation can be passively done in the repeater (i.e., withoutinitiating or forcing an oscillation), based on measurements thatindicate how close the repeater is to an oscillation. For example, therepeater can measure an amount of antenna feedback path loss and acurrent amount of gain in the repeater. Based on the antenna feedbackpath loss and the current amount of gain, a maximum gain can be set forthe repeater while maintaining a defined amount of oscillation margin.For example, the maximum gain level for the repeater can be set based onthe antenna feedback path loss as well as a repeater gain to avoid anoscillation in the repeater, since the repeater can begin to oscillateas the antenna feedback path loss approaches the repeater gain level. Bypassively setting the repeater gain (i.e., not forcing an oscillation),carriers and the network can benefit, as fewer problems would be causedon the network due to oscillations in the repeater. Since an oscillationcan cause a sudden and strong power and noise effect on a base stationof the network, initiating or forcing oscillations is not desirable, sopassively avoiding or preventing oscillations before they occur in therepeater can benefit the network. In addition, having a passive approachor solution can enable the repeater to increase its gain while beingconfigured to identify that the gain increase will not cause anoscillation in the repeater, which is not possible with previoussolutions that force an oscillation in the repeater.

In one example, the repeater can shut off or reduce its gain when thereis an oscillation, but with this passive approach or solution, therepeater would be able to test whether conditions have changed. Forexample, the repeater can determine whether an amount of antennafeedback path loss has changed or remains the same. When the antennafeedback path loss is increased (less feedback) (e.g., there is moreisolation due to an antenna being moved or an obstacle that waspreviously causing a reflection has since been moved), the repeater canincrease its gain without fear of oscillation. As a result, the repeatercan continue to operate at its maximum gain level while being configuredto determine that increasing the gain will not cause an oscillation inthe repeater.

In one example, the repeater can include software and/or hardware thatcause the repeater to sense the feedback paths (i.e., to determineantenna feedback path loss), which can allow the repeater to operate atits maximum gain level. For example, a user can walk past an antenna ofthe repeater, which can cause an oscillation feedback. At a later pointin time when the user is gone, the oscillation feedback would cease toexist. However, without this hardware/software detectability of thefeedback paths, the repeater may not be configured to identify whetherthe person is there or not, and in past solutions, the repeater wouldnot risk increasing the gain to avoid causing an oscillation. Here, withthe ability to continually or periodically measure the feedback paths,the repeater can determine whether a user is present, and determinewhether to increase or not increase the repeater gain while maintainingsafe operation.

FIG. 3 illustrates an example of a repeater 300 operable to measure anantenna feedback path loss 333 and set a maximum gain level with anoscillation margin based on the antenna feedback path loss 333. Therepeater 300 can be an FCC-compatible cellular signal repeater or signalbooster. The antenna feedback path loss 333 can be measured foroscillation avoidance or mitigation purposes. The repeater 300 caninclude a first antenna 310 communicatively coupled to a first port 312,and a second antenna 320 communicatively coupled to a second port 322.For example, the first antenna 310 can be an outside antenna or donorantenna, and the second antenna 320 can be an insider antenna or serverantenna, or vice versa. In this example, the first port 312 can be adonor port and the second port 322 can be a server port. The repeater300 can include a transmitter 330 communicatively coupled to the firstport 312, and a receiver 350 communicatively coupled to the second port322. The repeater 300 can include a controller 360 that is configured tocommunicate with the transmitter 330 and the receiver 350.

In an alternative configuration, the repeater 300 can include a firsttransceiver communicatively coupled to the first port 312, and a secondtransceiver communicatively coupled to the second port 322. The repeater300 can include a controller 360 that is configured to communicate withthe first transceiver and the second transceiver. The first and secondtransceivers can be cellular transceivers or ISM transceivers.

In one example, the repeater 300 can include a cellular signal amplifier340. The cellular signal amplifier 340 can include one or more uplinksignal paths and one or more downlink signal paths. The uplink signalpath(s) and the downlink signal path(s) can each include one or moreamplifiers (e.g., low noise amplifiers (LNAs), power amplifiers (PAs))and one or more bandpass filters for amplifying and filtering cellularsignals, respectively.

In one example, the transmitter 330 can transmit a path loss signal tobe used for measuring the antenna feedback path loss 333. The path losssignal can be transmitted on a downlink or on an uplink. The path losssignal can be a coded signal or a continuous wave (CW) signal. The pathloss signal can be transmitted away from the repeater 300. The receiver350 may detect some of the path loss signal transmitted from thetransmitter 330. For example, the receiver 350 can include or be coupledto a signal detector that detects the path loss signal. The controller360 can identify a first power level (a transmitted power) of the pathloss signal transmitted from the transmitter 330. For example, the pathloss signal can be transmitted at a known or predefined first powerlevel. The controller 360 can identify a second power level (a receivedpower) of the path loss signal received at the receiver 350. Forexample, a signal detector can detect the second power level of the pathloss signal, and this information can be provided to the controller 360.The controller 360 can determine the antenna feedback path loss 333 (indB) of the repeater 300 based on the first power level and the secondpower level (e.g., based on a difference between the first power leveland the second power level). In other words, the controller 360 cansubtract the transmitted power from the received power in order tocalculate the antenna feedback path loss 333. The controller 360 can seta maximum gain level (in dB) for the repeater 300 that is below theantenna feedback path loss 333 by a defined oscillation margin (in dB)to avoid an oscillation in the repeater 300. The controller 360 candetermine the maximum gain level by subtracting the defined oscillationmargin from the calculated antenna feedback path loss 333. The antennafeedback path loss 333 should be greater than the maximum gain level toavoid an oscillation in the repeater 300.

As an example, the repeater 300 can determine that the antenna feedbackpath loss is 80 dB and the gain of the repeater 300 is 70 dB. In thisexample, the repeater 300 is operating at an acceptable gain levelbecause there is an oscillation margin of 10 dB (i.e., the gain issubtracted from the antenna feedback path loss to determine theoscillation margin). As another example, when the calculated antennafeedback path loss is 80 dB and a current gain is 70 dB (and thereforean oscillation margin of 10 dB), but it is desirable for the repeater tohave an oscillation margin of 12 dB, the repeater 300 can adjust itsgain to 68 dB. In this case, in view of the antenna feedback path lossof 80 dB and the desired oscillation margin of 12 dB, the repeater 300can reduce its current gain of 70 dB to 68 dB in order to obtain thedesired oscillation margin of 12 dB. In another example, the calculatedantenna feedback path loss is 71 dB and a current gain is 70 dB. In thisexample, the resulting oscillation margin of 1 dB can be insufficient,as it can be desirable to have at least a 5 or 6 dB oscillation margin.Therefore, the repeater 300 can determine a maximum gain level at whichto operate while maintaining an oscillation margin, in view of themeasured antenna feedback path loss.

In one example, the controller 360 can increase the maximum gain levelwhen the antenna feedback path loss 333 is increased while avoiding anoscillation in the repeater 300. In other words, when the antennafeedback path loss 333 increases, the maximum gain level can also beincreased while maintaining the desired oscillation margin. In anotherexample, the controller 360 can decrease the maximum gain level when theantenna feedback path loss 333 is decreased. In other words, when theantenna feedback path loss 333 decreases, not decreasing the maximumgain level can result in an oscillation in the repeater 300.

In one example, the antenna feedback path loss 333 can indicate anamount of port-to-port system isolation. In other words, the antennafeedback path loss 333 can indicate an amount of isolation between thefirst antenna 310 (e.g., donor antenna) and the second antenna 320(e.g., server antenna). The amount of isolation can account for loss oncoaxial cable(s) of the repeater 333 and gain of the first and secondantennas 310, 320. As a result, the antenna feedback path loss 333 canbe measured between the first port 312 and the second port 322 of therepeater 300.

As an example, when a user walks by the repeater 300, this can result ina reflection that causes the controller 360 to identify a decreasedantenna feedback path loss 333. When this occurs, the controller 360 canreduce the maximum gain level. When there is no user in front of or inproximity to the repeater 300 that causes the reflection, the controller360 can identify an increased antenna feedback path loss 333. When thisoccurs, the controller 360 can increase the maximum gain level.

In one configuration, when the repeater 300 is initially powered on(i.e., during startup or calibration), RF signal paths in the repeater300 can be disabled to avoid oscillations. The transmitter 330 and thereceiver 350 can be initially turned on, and the antenna feedback pathloss 333 can be measured (while the RF signal paths are disabled). Thecontroller 360 can set a maximum gain level while maintaining a definedoscillation margin, in view of the measured antenna feedback path loss333. Then the RF signal paths in the repeater 300 can be enabled. Bysetting the maximum gain level based on the measured antenna feedbackpath loss 333 upon startup, an oscillation can be avoided in therepeater 300 during startup. In other words, the repeater 300 canincrease its gain based on the measured antenna feedback path loss 333without risk of causing an oscillation in the repeater 300. Thecontroller 360 can identify how much the gain can be increased by (e.g.,10 dB) with a confidence that the increased gain will not cause anoscillation in the repeater 300.

In one example, after startup, the controller 360 can continue tomeasure the antenna feedback path loss 333 over time and adjust themaximum gain level periodically as needed. For example, the controller360 can determine subsequent antenna feedback path losses and setsubsequent maximum gain levels for the repeater 300 in accordance with adefined periodicity (e.g., every few milliseconds, seconds or minutes).Therefore, the transmitter 330 and the receiver 350 can continue toperiodically transmit/receive path loss signals, and the antennafeedback path losses can be measured over the period of time.

In one configuration, the controller 360 can detect patterns incalculated antenna feedback path losses over a period of time, which canenable quicker or automated repeater gain adjustments. The controller360 can set a maximum gain level for the repeater 300 in accordance witha defined pattern of calculated feedback losses. For example, thecontroller 360 can determine that an antenna feedback path loss islikely to decrease at certain times of the day (e.g., due to anincreased number of users in proximity to the repeater 300 and causingmore reflection), based on measured antenna feedback path losses thatare collected over the period of time. When the antenna feedback pathloss is decreased, it is desirable to decrease the repeater's gain toavoid triggering an oscillation. In addition, the controller 360 can beconfigured to identify that these periods of decreased antenna feedbackpath loss are likely to occur for a certain period of time (e.g., 10minutes), at which point, the antenna feedback path loss is likely toincrease. When the antenna feedback path loss is increased, it isdesirable to increase the repeater's gain. In this example, thecontroller 360 can automatically decrease the maximum gain level for therepeater 300 during this expected time period, and when this time periodis over, the controller 360 can automatically increase the maximum gainlevel for the repeater 300.

In one example, the repeater 300 can be a marine repeater or marinesignal booster, and can be included in a water vehicle (e.g., a boat).In rough waters, the repeater 300 can tip or slightly move due to waves.When the repeater 300 is tipped or slightly moved, the antenna feedbackpath loss 333 can change due to reflections from the water. Therefore,when the repeater 300 is tipped, the maximum gain level can be reduceddue to reduced antenna feedback path losses. In one example, rhythms andpatterns of increases and decreases in antenna feedback path loss due towaves can be determined over a period of time, and the controller 360can automatically adjust (e.g., increase or decrease) the maximum gainlevel to account for expected increases and decreases in antennafeedback path loss. In this environment, without the ability toperiodically measure the antenna feedback path loss and dynamicallyadjust the maximum gain level based on the antenna feedback path loss,the repeater 300 would reduce its gain and operate at that reduced gainlevel for an extended period of time (even when the antenna feedbackpath loss is later increased) to avoid causing an oscillation in therepeater 300.

In one configuration, the transmitter 330 and the receiver 350 can be anindustrial, scientific, and medical (ISM) transmitter/receiver, and thepath loss signal transmitted from the transmitter 330 to the receiver350 can be an ISM path loss signal (an out of cellular band). The ISMpath loss signal can be transmitted in a band or frequency range that isnot a cellular band or frequency range in which the cellular signalamplifier 340 is amplifying cellular signals. As an example, the ISMtransmitter/receiver can transmit/receive an ISM path loss signal on afrequency between 20 MHz and 1 GHz.

In one example, the transmitter 330 and the receiver 350 can be an ISMtransmitter and an ISM receiver, respectively. In another example, thetransmitter 330 and the receiver 350 can be an ISM transmitter and anISM receiver with a mixer, and can have a common synthesizer. In yetanother example, instead of an ISM transmitter and an ISM receiver, asynthesizer can be coupled to the first port 312 and a detector can becoupled to the second port 322.

In one example, an ISM path loss signal transmitted from the transmitter330 is transmitted away from the repeater 300 and is not passed throughthe cellular signal amplifier 340. In the case that some of the ISM pathloss signal is detected at the receiver 350, the ISM path loss signalcan be filtered out and does not pass through the cellular signalamplifier 340. In other words, the cellular signal amplifier 340 can beconfigured to filter out ISM frequencies. As a result, the ISM path losssignal is not amplified by the cellular signal amplifier 340. The ISMpath loss signal can be transmitted for a brief period of time, and arepeater transmission can be turned on while an ISM transmission occurs.Alternatively, the ISM path loss signal can be transmitted against anamplification path, so the ISM path loss signal does not becomeamplified through the repeater 300.

In one example, when the path loss signal transmitted from thetransmitter 330 to the receiver 350 is an ISM path loss signal, thecontroller 360 can convert or adjust the calculated antenna feedbackpath loss 333 for a cellular frequency. In other words, typical signalsthat are passing through the cellular signal amplifier 340 are cellularsignals and not ISM signals, but the calculated antenna feedback pathloss 333 is for an ISM path loss signal. As a result, the calculatedantenna feedback path loss 333 is not entirely accurate for cellularsignals that pass through the cellular signal amplifier 340. Therefore,the controller 360 can perform a conversion to calculate an antennafeedback path loss 333 for cellular signals using the calculated antennafeedback path loss for the ISM path loss signal. In other words, thecontroller 360 can extrapolate the antenna feedback path loss 333 forcellular frequencies using, e.g., a straight path loss conversiontechnique, which can account for an antenna and/or coaxial cable deltaas well.

In one example, the controller 360 can determine the antenna feedbackpath loss 333 for an ISM path loss signal, and extrapolate thedetermined antenna feedback path loss 333 to an in-band cellularfrequency path loss to set the maximum gain level for the repeater 300.In other words, the controller 360 can calibrate an ISM path loss thatcorresponds to the antenna feedback path loss 333 to the in-bandcellular frequency path loss by measuring the ISM path loss when theoscillation (e.g., a cellular oscillation) occurs in the repeater 300.In another example, as an alternative to the extrapolation technique,the controller 360 can determine an antenna feedback path loss for anout-of-band signal, and then use the antenna feedback path loss for anout-of-band frequency of the out-of-band signal to determine a secondantenna feedback path loss for an in-band cellular frequency.

In another example, the repeater 300 can use multiple ISM bands (e.g.,400 MHz, 900 MHz, 2400 MHz) to increase data confidence and interpolatethe antenna feedback path loss 333 instead of extrapolating the antennafeedback path loss 333. In yet another example, the antenna feedbackpath loss 333 can be determined based on a measured time for the ISMpath loss signal to propagate and how far the ISM path loss signaltravels, while calibrating out a coaxial cable propagation time.

In one configuration, the path loss signal transmitted from thetransmitter 330 to the receiver 350 can be an in-band cellular signal(i.e., a path loss signal that is included in an operating cellularfrequency range of the repeater 300). However, the FCC Consumer Boosterrules can restrict a power level of the cellular path loss signal and anamount of time for transmitting the cellular path loss signal. Thecellular path loss signal can be transmitted in a random manner, as itcan be difficult to transmit the cellular path loss signal withregularity and still comply with the FCC Consumer Booster rules. As anon-limiting example, the cellular path loss signal can be transmittedrandomly for approximately 10 uS about every 18 mS. As anothernon-limiting example, the cellular path loss signal(s) can betransmitted for not more than a total of 2 seconds every hour to complywith the FCC Code of Federal Regulations (CFR) 47 part 15 limits(irrespective of a number of individual cellular path loss signaltransmissions). The cellular path loss signal can be transmitted at areduced power level, but at a sufficient power level that is detectableand above the noise floor. The cellular path loss signal can betransmitted on the bands or frequency ranges served by the repeater 300,with the exception of certain frequency ranges (e.g., a minimalfrequency range in band 4), as long as the path loss signal transmissionis in accordance with the FCC Consumer Booster rules. When the cellularpath loss signal is transmitted for calculating the antenna feedbackpath loss 333, the calculated antenna feedback path loss 333 is accurateand does not have to be extrapolated (in contrast to when an ISM pathloss signal is transmitted for calculating the antenna feedback pathloss 333).

In one example, when the transmitted path loss signal is an in-bandcellular path loss signal, a worst-case feedback frequency can beidentified during startup, which can prevent sweeping a whole band eachtime. In one example, a sweep of the whole band can be performedperiodically. In another example, a receiver in the repeater 300 (e.g.,the receiver 350) can scan for open channels and notify a transmitter inthe repeater 300 (e.g., the transmitter 330) on which channel totransmit. In a further example, the repeater 300 can transmit on adownlink band only, which can minimize the potential for carrier networkdisruption.

In an alternative configuration, the controller 360 can detect anoscillation that occurs in the repeater 300. After the oscillationoccurs, the transmitter 330 can transmit a path loss signal, which canbe detected by the receiver 350. The controller 360 can identify a firstpower level of the path loss signal transmitted from the transmitter330, as well as a second power level of the path loss signal received atthe receiver 350. The controller 360 can determine, after theoscillation occurs in the repeater 300, an antenna feedback path loss333 based on the first power level and the second power level (e.g., adifference between the first power level and the second power level).The controller 360 can associate the calculated antenna feedback pathloss 333 with the oscillation. In other words, the controller 360 can beconfigured to identify that when a certain gain is applied, the repeater300 will experience an oscillation when the antenna feedback path loss333 reaches that calculated level. When the antenna feedback path loss333 is below that calculated level and the certain gain is applied, therepeater 300 will not experience an oscillation. The controller 360 canset a maximum gain level for the repeater 300 that is below the antennafeedback path loss 333 (at which the controller 360 determines anoscillation will occur) by a defined oscillation margin to avoid asubsequent oscillation in the repeater 300. In this configuration, therepeater 300 can wait until an oscillation occurs, and the antennacalculated antenna feedback path loss when that oscillation occurs canserve as a baseline for selecting the maximum gain level in view of adesired oscillation margin.

In other words, in the above example, if/when the repeater 300oscillates on a certain cellular band, an ISM path loss signal can besent to “calibrate” the antenna feedback path loss 333 for the cellularband that experienced the oscillation. The repeater 300 can look forthat antenna feedback path loss 333 and adjust a repeater gain to bebelow the antenna feedback path loss 333 (by a defined oscillationmargin). Thus, in this alternative example, an oscillation in therepeater 300 can enable the antenna feedback path loss 333 of therepeater 300 to be calibrated.

In one example, a measured feedback loss 333 can be displayed to uservia a display screen, which can aid the user during installation or forpost-installation trouble-shooting. For example, a green/yellow/redindicator light can be displayed to show an amount of oscillation marginavailable for the repeater 300. Typically during installation, aninstaller would measure an amount of antenna feedback path loss, and theinstaller would have to plug in the repeater 300 and see whether anoscillation occurs. Here, the installer can be provided with morereal-time feedback on how far away the repeater 300 is from oscillationduring installation.

FIG. 4 illustrates an example of a repeater 400 operable to measure anantenna feedback path loss 433 and set a maximum gain level with anoscillation margin based on the antenna feedback path loss 433. Therepeater 400 can include a first antenna 410 communicatively coupled toa first port 412, and a second antenna 420 communicatively coupled to asecond port 422. For example, the first antenna 410 can be an outsideantenna or donor antenna, and the second antenna 420 can be an insiderantenna or server antenna, or vice versa. In this example, the firstport 412 can be a donor port and the second port 422 can be a serverport. The repeater 400 can include a transceiver 450 communicativelycoupled to one of the first port 412 or the second port 422. In theexample shown, the transceiver 450 is communicatively coupled to thesecond port 422. In addition, the repeater 400 can include a cellularsignal amplifier 440 and a controller 460.

In one example, the controller 460 can identify a first power level of apath loss signal transmitted from the transceiver 450. The controller460 can identify a second power level of the path loss signal receivedat the transceiver 450 through the repeater 400 (e.g., through the firstantenna 410 and the cellular signal amplifier 440). The controller 460can determine the antenna feedback path loss 433 of the repeater 400based on the first power level and the second power level. Thecontroller 460 can set a maximum gain level for the repeater 400 basedon the antenna feedback path loss 433 to avoid an oscillation in therepeater 400.

FIG. 5 illustrates functionality of a repeater operable to detectantenna feedback path loss. The repeater can include a first port. Therepeater can include a second port. The repeater can include atransmitter communicatively coupled to the first port. The transmittercan be configured to transmit a path loss signal. The repeater caninclude a receiver communicatively coupled to the second port, thereceiver configured to receive the path loss signal transmitted by thetransmitter. The repeater can include a controller. The controller canidentify a first power level of the signal transmitted from thetransmitter, as in block 510. The controller can identify a second powerlevel of the signal received at the receiver, as in block 520. Thecontroller can determine an antenna feedback path loss of the repeaterbased on the first power level and the second power level, as in block530. The controller can set a maximum gain level for the repeater basedon the antenna feedback path loss to avoid an oscillation in therepeater, as in block 540.

FIG. 6 illustrates functionality of a repeater. The repeater can includea first port. The repeater can include a second port. The repeater caninclude a transmitter communicatively coupled to the first port. Therepeater can include a receiver communicatively coupled to the secondport. The repeater can include a controller. The controller can detectan oscillation in the repeater, as in block 610. The controller canidentify a first power level of a signal transmitted from thetransmitter, as in block 620. The controller can identify a second powerlevel of the signal received at the receiver, as in block 630. Thecontroller can determine, after the oscillation occurs in the repeater,an antenna feedback path loss of the repeater based on the first powerlevel and the second power level, wherein the antenna feedback path lossis associated with the oscillation, as in block 640. The controller canset a maximum gain level for the repeater based on the antenna feedbackpath loss to avoid a subsequent oscillation in the repeater, as in block650.

FIG. 7 illustrates functionality of a repeater. The repeater can includea first port. The repeater can include a second port. The repeater caninclude a transceiver communicatively coupled to one of the first portor the second port. The transceiver can be configured to transmit a pathloss signal and detect the path loss signal. The repeater can include acontroller. The controller can identify a first power level of the pathloss signal transmitted from the transceiver, as in block 710. Thecontroller can identify a second power level of the path loss signalreceived at the transceiver through the repeater, as in block 720. Thecontroller can determine an antenna feedback path loss of the repeaterbased on the first power level and the second power level, as in block730. The controller can set a maximum gain level for the repeater basedon the feedback path loss to avoid an oscillation in the repeater, as inblock 740.

FIG. 8 provides an example illustration of the wireless device, such asa user equipment (UE), a mobile station (MS), a mobile communicationdevice, a tablet, a handset, a wireless transceiver coupled to aprocessor, or other type of wireless device. The wireless device caninclude one or more antennas configured to communicate with a node ortransmission station, such as an access point (AP), a base station (BS),an evolved Node B (eNB), a baseband unit (BBU), a remote radio head(RRH), a remote radio equipment (RRE), a relay station (RS), a radioequipment (RE), a remote radio unit (RRU), a central processing module(CPM), or other type of wireless wide area network (WWAN) access point.The wireless device can communicate using separate antennas for eachwireless communication standard or shared antennas for multiple wirelesscommunication standards. The wireless device can communicate in awireless local area network (WLAN), a wireless personal area network(WPAN), and/or a WWAN.

FIG. 8 also provides an illustration of a microphone and one or morespeakers that can be used for audio input and output from the wirelessdevice. The display screen can be a liquid crystal display (LCD) screen,or other type of display screen such as an organic light emitting diode(OLED) display. The display screen can be configured as a touch screen.The touch screen can use capacitive, resistive, or another type of touchscreen technology. An application processor and a graphics processor canbe coupled to internal memory to provide processing and displaycapabilities. A non-volatile memory port can also be used to providedata input/output options to a user. The non-volatile memory port canalso be used to expand the memory capabilities of the wireless device. Akeyboard can be with the wireless device or wirelessly connected to thewireless device to provide additional user input. A virtual keyboard canalso be provided using the touch screen.

EXAMPLES

The following examples pertain to specific technology embodiments andpoint out specific features, elements, or actions that can be used orotherwise combined in achieving such embodiments.

Example 1 includes a repeater operable to detect antenna feedback pathloss, the repeater comprising: a first port; a second port; atransmitter communicatively coupled to the first port, the transmitterconfigured to transmit a path loss signal; a receiver communicativelycoupled to the second port, the receiver configured to receive the pathloss signal transmitted by the transmitter; and a controller configuredto: identify a first power level of the signal transmitted from thetransmitter; identify a second power level of the signal received at thereceiver; determine an antenna feedback path loss of the repeater basedon the first power level and the second power level; and set a maximumgain level for the repeater based in part on the antenna feedback pathloss to avoid an oscillation in the repeater.

Example 2 includes the repeater of Example 1, wherein the controller isconfigured to set the maximum gain level for the repeater to be below arepeater oscillation level by a defined oscillation margin, wherein therepeater oscillation level is a difference between the antenna feedbackpath loss plus a repeater gain and the defined oscillation margin.

Example 3 includes the repeater of any of Examples 1 to 2, wherein thecontroller is configured to: increase the maximum gain level for therepeater when the antenna feedback path loss is increased while avoidingthe oscillation in the repeater; or decrease the maximum gain level forthe repeater when the antenna feedback path loss is decreased.

Example 4 includes the repeater of any of Examples 1 to 3, wherein thecontroller is configured to: disable one or more radio frequency (RF)signal paths of the repeater before a maximum gain level is set; andenable the one or more RF signal paths after the maximum gain level isset.

Example 5 includes the repeater of any of Examples 1 to 4, wherein thecontroller is configured to: determine the antenna feedback path lossand set the maximum gain level when the repeater is powered on, whereinthe oscillation in the repeater is avoided when the repeater is poweredon; and determine a subsequent antenna feedback path loss and set asubsequent maximum gain level for the repeater in accordance with adefined periodicity.

Example 6 includes the repeater of any of Examples 1 to 5, wherein thetransmitter is configured to transmit the signal in a periodic or randommanner when the path loss signal is a cellular signal, and the signal isincluded in an operating cellular frequency range of the repeater.

Example 7 includes the repeater of any of Examples 1 to 6, wherein thecontroller is configured to set the maximum gain level for the repeaterin accordance with a defined pattern of antenna feedback path losses forthe repeater.

Example 8 includes the repeater of any of Examples 1 to 7, wherein thesignal transmitted by the transmitter and received at the receiver is anout-of-band industrial, scientific, and medical (ISM) signal or anin-band cellular signal.

Example 9 includes the repeater of any of Examples 1 to 8, wherein thecontroller is configured to: determine the antenna feedback path lossfor an out-of-band signal; and use the antenna feedback path loss for anout-of-band frequency of the out-of-band signal to determine a secondantenna feedback path loss for an in-band cellular frequency.

Example 10 includes the repeater of any of Examples 1 to 9, wherein thecontroller is configured to: determine multiple antenna feedback pathlosses based on multiple out-of-band signals transmitted by thetransmitter and received at the receiver; and interpolate the determinedmultiple antenna feedback path losses to an in-band cellular frequencypath loss to set the maximum gain level for the repeater.

Example 11 includes the repeater of any of Examples 1 to 10, furthercomprising: a first antenna communicatively coupled to the first port,the path loss signal being transmitted from the transmitter via thefirst antenna; and a second antenna communicatively coupled to thesecond port, the path loss signal being received at the receiver via thesecond antenna.

Example 12 includes the repeater of any of Examples 1 to 11, wherein therepeater is a Federal Communications Commission (FCC)-compatiblecellular signal repeater.

Example 13 includes the repeater of any of Examples 1 to 12, wherein thepath loss signal is transmitted in a downlink.

Example 14 includes the repeater of any of Examples 1 to 13, furthercomprising an indication to show an amount of oscillation marginavailable for the repeater based on the antenna feedback path loss andthe maximum gain level set for the repeater.

Example 15 includes the repeater of any of Examples 1 to 14, wherein:the receiver is further configured to scan for open channels; and thetransmitter is further configured to transmit the path loss signal onone of the open channels.

Example 16 includes a repeater, comprising: a first port; a second port;a transmitter communicatively coupled to the first port; a receivercommunicatively coupled to the second port; and a controller configuredto: detect an oscillation in the repeater; identify a first power levelof a signal transmitted from the transmitter, wherein the signal is alicensed or unlicensed radio frequency (RF) signal; identify a secondpower level of the signal received at the receiver; determine, after theoscillation occurs in the repeater, an antenna feedback path loss of therepeater based on the first power level and the second power level,wherein the antenna feedback path loss is associated with theoscillation; and set a maximum gain level for the repeater based in parton the antenna feedback path loss to avoid a subsequent oscillation inthe repeater.

Example 17 includes the repeater of Example 16, wherein the controlleris configured to set the maximum gain level for the repeater to be belowa repeater oscillation level by a defined oscillation margin, whereinthe repeater oscillation level is a difference between the antennafeedback path loss plus a repeater gain and the defined oscillationmargin.

Example 18 includes the repeater of any of Examples 16 to 17, whereinthe controller is configured to: increase the maximum gain level for therepeater when the antenna feedback path loss is increased while avoidingthe subsequent oscillation in the repeater; or decrease the maximum gainlevel for the repeater when the antenna feedback path loss is decreased.

Example 19 includes the repeater of any of Examples 16 to 18, whereinthe controller is configured to determine a subsequent antenna feedbackpath loss and set a subsequent maximum gain level for the repeater inaccordance with a defined periodicity.

Example 20 includes the repeater of any of Examples 16 to 19, whereinthe signal transmitted by the transmitter and received at the receiveris an industrial, scientific, and medical (ISM) signal or a cellularsignal.

Example 21 includes the repeater of any of Examples 16 to 20, whereinthe transmitter is configured to transmit the signal and the receiver isconfigured to receive the signal after the oscillation occurs in therepeater.

Example 22 includes the repeater of any of Examples 16 to 21, whereinthe controller is configured to: determine the antenna feedback pathloss for an out-of-band signal; and use the antenna feedback path lossfor an out-of-band frequency of the out-of-band signal to determine asecond antenna feedback path loss for an in-band cellular frequency.

Example 23 includes the repeater of any of Examples 16 to 22, whereinthe controller is configured to calibrate an ISM path loss thatcorresponds to the antenna feedback path loss to the in-band cellularfrequency path loss by measuring the ISM path loss when the oscillationoccurs in the repeater, wherein the oscillation is a cellularoscillation.

Example 24 includes a repeater, comprising: a first port; a second port;a transceiver communicatively coupled to one of the first port or thesecond port, the transceiver configured to transmit a path loss signaland detect the path loss signal; and a controller configured to:identify a first power level of the path loss signal transmitted fromthe transceiver; identify a second power level of the path loss signalreceived at the transceiver through the repeater; determine an antennafeedback path loss of the repeater based on the first power level andthe second power level; and set a maximum gain level for the repeaterbased in part on the feedback path loss to avoid an oscillation in therepeater.

Example 25 includes the repeater of Example 24, wherein the path losssignal is an in-band cellular signal.

Example 26 includes the repeater of any of Examples 24 to 25, whereinthe transceiver is configured to transmit the path loss signal at apower level permitted under Federal Communications Commission (FCC) Codeof Federal Regulations (CFR) 47 Part 15.

Various techniques, or certain aspects or portions thereof, can take theform of program code (i.e., instructions) embodied in tangible media,such as floppy diskettes, compact disc-read-only memory (CD-ROMs), harddrives, non-transitory computer readable storage medium, or any othermachine-readable storage medium wherein, when the program code is loadedinto and executed by a machine, such as a computer, the machine becomesan apparatus for practicing the various techniques. Circuitry caninclude hardware, firmware, program code, executable code, computerinstructions, and/or software. A non-transitory computer readablestorage medium can be a computer readable storage medium that does notinclude signal. In the case of program code execution on programmablecomputers, the computing device can include a processor, a storagemedium readable by the processor (including volatile and non-volatilememory and/or storage elements), at least one input device, and at leastone output device. The volatile and non-volatile memory and/or storageelements can be a random-access memory (RAM), erasable programmable readonly memory (EPROM), flash drive, optical drive, magnetic hard drive,solid state drive, or other medium for storing electronic data. One ormore programs that can implement or utilize the various techniquesdescribed herein can use an application programming interface (API),reusable controls, and the like. Such programs can be implemented in ahigh level procedural or object oriented programming language tocommunicate with a computer system. However, the program(s) can beimplemented in assembly or machine language, if desired. In any case,the language can be a compiled or interpreted language, and combinedwith hardware implementations.

As used herein, the term processor can include general purposeprocessors, specialized processors such as VLSI, FPGAs, or other typesof specialized processors, as well as base band processors used intransceivers to send, receive, and process wireless communications.

It should be understood that many of the functional units described inthis specification have been labeled as modules, in order to moreparticularly emphasize their implementation independence. For example, amodule can be implemented as a hardware circuit comprising customvery-large-scale integration (VLSI) circuits or gate arrays,off-the-shelf semiconductors such as logic chips, transistors, or otherdiscrete components. A module can also be implemented in programmablehardware devices such as field programmable gate arrays, programmablearray logic, programmable logic devices or the like.

In one example, multiple hardware circuits or multiple processors can beused to implement the functional units described in this specification.For example, a first hardware circuit or a first processor can be usedto perform processing operations and a second hardware circuit or asecond processor (e.g., a transceiver or a baseband processor) can beused to communicate with other entities. The first hardware circuit andthe second hardware circuit can be incorporated into a single hardwarecircuit, or alternatively, the first hardware circuit and the secondhardware circuit can be separate hardware circuits.

Modules can also be implemented in software for execution by varioustypes of processors. An identified module of executable code can, forinstance, comprise one or more physical or logical blocks of computerinstructions, which can, for instance, be organized as an object,procedure, or function. Nevertheless, the executables of an identifiedmodule need not be physically located together, but can comprisedisparate instructions stored in different locations which, when joinedlogically together, comprise the module and achieve the stated purposefor the module.

Indeed, a module of executable code can be a single instruction, or manyinstructions, and can even be distributed over several different codesegments, among different programs, and across several memory devices.Similarly, operational data can be identified and illustrated hereinwithin modules, and can be embodied in any suitable form and organizedwithin any suitable type of data structure. The operational data can becollected as a single data set, or can be distributed over differentlocations including over different storage devices, and can exist, atleast partially, merely as electronic signals on a system or network.The modules can be passive or active, including agents operable toperform desired functions.

Reference throughout this specification to “an example” or “exemplary”means that a particular feature, structure, or characteristic describedin connection with the example is included in at least one embodiment ofthe present invention. Thus, appearances of the phrases “in an example”or the word “exemplary” in various places throughout this specificationare not necessarily all referring to the same embodiment.

As used herein, a plurality of items, structural elements, compositionalelements, and/or materials can be presented in a common list forconvenience. However, these lists should be construed as though eachmember of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as ade facto equivalent of any other member of the same list solely based ontheir presentation in a common group without indications to thecontrary. In addition, various embodiments and example of the presentinvention can be referred to herein along with alternatives for thevarious components thereof. It is understood that such embodiments,examples, and alternatives are not to be construed as de factoequivalents of one another, but are to be considered as separate andautonomous representations of the present invention.

Furthermore, the described features, structures, or characteristics canbe combined in any suitable manner in one or more embodiments. In thefollowing description, numerous specific details are provided, such asexamples of layouts, distances, network examples, etc., to provide athorough understanding of embodiments of the invention. One skilled inthe relevant art will recognize, however, that the invention can bepracticed without one or more of the specific details, or with othermethods, components, layouts, etc. In other instances, well-knownstructures, materials, or operations are not shown or described indetail to avoid obscuring aspects of the invention.

While the forgoing examples are illustrative of the principles of thepresent invention in one or more particular applications, it will beapparent to those of ordinary skill in the art that numerousmodifications in form, usage and details of implementation can be madewithout the exercise of inventive faculty, and without departing fromthe principles and concepts of the invention. Accordingly, it is notintended that the invention be limited, except as by the claims setforth below.

What is claimed is:
 1. A repeater operable to detect antenna feedbackpath loss, the repeater comprising: a first port; a second port; atransmitter communicatively coupled to the first port, the transmitterconfigured to transmit a path loss signal; a receiver communicativelycoupled to the second port, the receiver configured to receive the pathloss signal transmitted by the transmitter; and a controller configuredto: identify a first power level of the signal transmitted from thetransmitter; identify a second power level of the signal received at thereceiver; determine an antenna feedback path loss of the repeater basedon the first power level and the second power level; and set a maximumgain level for the repeater based in part on the antenna feedback pathloss to avoid an oscillation in the repeater, wherein the controller isconfigured to set the maximum gain level for the repeater to be below arepeater oscillation level by a defined oscillation margin, wherein therepeater oscillation level is a difference between the antenna feedbackpath loss plus a repeater gain and the defined oscillation margin. 2.The repeater of claim 1, wherein the controller is configured to:increase the maximum gain level for the repeater when the antennafeedback path loss is increased while avoiding the oscillation in therepeater; or decrease the maximum gain level for the repeater when theantenna feedback path loss is decreased.
 3. The repeater of claim 1,wherein the controller is configured to: disable one or more radiofrequency (RF) signal paths of the repeater before a maximum gain levelis set; and enable the one or more RF signal paths after the maximumgain level is set.
 4. The repeater of claim 1, wherein the controller isconfigured to: determine the antenna feedback path loss and set themaximum gain level when the repeater is powered on, wherein theoscillation in the repeater is avoided when the repeater is powered on;and determine a subsequent antenna feedback path loss and set asubsequent maximum gain level for the repeater in accordance with adefined periodicity.
 5. The repeater of claim 1, wherein the transmitteris configured to transmit the signal in a periodic or random manner whenthe path loss signal is a cellular signal, and the signal is included inan operating cellular frequency range of the repeater.
 6. The repeaterof claim 1, wherein the controller is configured to set the maximum gainlevel for the repeater in accordance with a defined pattern of antennafeedback path losses for the repeater.
 7. The repeater of claim 1,wherein the signal transmitted by the transmitter and received at thereceiver is an out-of-band industrial, scientific, and medical (ISM)signal or an in-band cellular signal.
 8. The repeater of claim 1,wherein the controller is configured to: determine the antenna feedbackpath loss for an out-of-band signal; and use the antenna feedback pathloss for an out-of-band frequency of the out-of-band signal to determinea second antenna feedback path loss for an in-band cellular frequency.9. The repeater of claim 1, wherein the controller is configured to:determine multiple antenna feedback path losses based on multipleout-of-band signals transmitted by the transmitter and received at thereceiver; and interpolate the determined multiple antenna feedback pathlosses to an in-band cellular frequency path loss to set the maximumgain level for the repeater.
 10. The repeater of claim 1, furthercomprising: a first antenna communicatively coupled to the first port,the path loss signal being transmitted from the transmitter via thefirst antenna; and a second antenna communicatively coupled to thesecond port, the path loss signal being received at the receiver via thesecond antenna.
 11. The repeater of claim 1, wherein the repeater is aFederal Communications Commission (FCC)-compatible cellular signalrepeater.
 12. The repeater of claim 1, wherein the path loss signal istransmitted in a downlink.
 13. The repeater of claim 1, furthercomprising an indication to show an amount of oscillation marginavailable for the repeater based on the antenna feedback path loss andthe maximum gain level set for the repeater.
 14. The repeater of claim1, wherein: the receiver is further configured to scan for openchannels; and the transmitter is further configured to transmit the pathloss signal on one of the open channels.
 15. A repeater, comprising: afirst port; a second port; a transmitter communicatively coupled to thefirst port; a receiver communicatively coupled to the second port; and acontroller configured to: detect an oscillation in the repeater;identify a first power level of a signal transmitted from thetransmitter, wherein the signal is a licensed or unlicensed radiofrequency (RF) signal; identify a second power level of the signalreceived at the receiver; determine, after the oscillation occurs in therepeater, an antenna feedback path loss of the repeater based on thefirst power level and the second power level, wherein the antennafeedback path loss is associated with the oscillation; and set a maximumgain level for the repeater based in part on the antenna feedback pathloss to avoid a subsequent oscillation in the repeater, wherein thecontroller is configured to: disable one or more radio frequency (RF)signal paths of the repeater before a maximum gain level is set; andenable the one or more RF signal paths after the maximum gain level isset.
 16. The repeater of claim 15, wherein the controller is configuredto set the maximum gain level for the repeater to be below a repeateroscillation level by a defined oscillation margin, wherein the repeateroscillation level is a difference between the antenna feedback path lossplus a repeater gain and the defined oscillation margin.
 17. Therepeater of claim 15, wherein the controller is configured to: increasethe maximum gain level for the repeater when the antenna feedback pathloss is increased while avoiding the subsequent oscillation in therepeater; or decrease the maximum gain level for the repeater when theantenna feedback path loss is decreased.
 18. The repeater of claim 15,wherein the controller is configured to determine a subsequent antennafeedback path loss and set a subsequent maximum gain level for therepeater in accordance with a defined periodicity.
 19. The repeater ofclaim 15, wherein the signal transmitted by the transmitter and receivedat the receiver is an industrial, scientific, and medical (ISM) signalor a cellular signal.
 20. The repeater of claim 15, wherein thetransmitter is configured to transmit the signal and the receiver isconfigured to receive the signal after the oscillation occurs in therepeater.
 21. The repeater of claim 15, wherein the controller isconfigured to: determine the antenna feedback path loss for anout-of-band signal; and use the antenna feedback path loss for anout-of-band frequency of the out-of-band signal to determine a secondantenna feedback path loss for an in-band cellular frequency.
 22. Therepeater of claim 21, wherein the controller is configured to calibratean ISM path loss that corresponds to the antenna feedback path loss tothe in-band cellular frequency path loss by measuring the ISM path losswhen the oscillation occurs in the repeater, wherein the oscillation isa cellular oscillation.
 23. A repeater, comprising: a first port; asecond port; a transceiver communicatively coupled to one of the firstport or the second port, the transceiver configured to transmit a pathloss signal and detect the path loss signal; and a controller configuredto: identify a first power level of the path loss signal transmittedfrom the transceiver; identify a second power level of the path losssignal received at the transceiver through the repeater; determine anantenna feedback path loss of the repeater based on the first powerlevel and the second power level; determine the antenna feedback pathloss for an out-of-band signal; and use the antenna feedback path lossfor an out-of-band frequency of the out-of-band signal to determine asecond antenna feedback path loss for an in-band cellular frequency; andset a maximum gain level for the repeater based in part on the feedbackpath loss to avoid an oscillation in the repeater.
 24. The repeater ofclaim 23, wherein the path loss signal is an in-band cellular signal.25. The repeater of claim 23, wherein the transceiver is configured totransmit the path loss signal at a power level permitted under FederalCommunications Commission (FCC) Code of Federal Regulations (CFR) 47Part
 15. 26. A repeater operable to detect antenna feedback path loss,the repeater comprising: a first port; a second port; a transmittercommunicatively coupled to the first port, the transmitter configured totransmit a path loss signal; a receiver communicatively coupled to thesecond port, the receiver configured to receive the path loss signaltransmitted by the transmitter; and a controller configured to: identifya first power level of the signal transmitted from the transmitter;identify a second power level of the signal received at the receiver;determine an antenna feedback path loss of the repeater based on thefirst power level and the second power level; and set a maximum gainlevel for the repeater based in part on the antenna feedback path lossto avoid an oscillation in the repeater; and an indication to show anamount of oscillation margin available for the repeater based on theantenna feedback path loss and the maximum gain level set for therepeater.